INTEMA   05428
INSTITUTO DE INVESTIGACIONES EN CIENCIA Y TECNOLOGIA DE MATERIALES
Unidad Ejecutora - UE
congresos y reuniones científicas
Título:
Bilayered electrospun polymeric vascular grafts with biomimetic behavior
Autor/es:
P.C. CARACCIOLO; G. BALAY; D. SUAREZ BAGNASCO; L. CYMBERKNOP; R.L. ARMENTANO; F. MONTINI BALLARIN; G. RIVERO; C.A. NEGREIRA
Lugar:
Foz de Iguazú, Brasil
Reunión:
Congreso; 9° COLAOB - Congresso Latino-Americano de Orgãos Artificiais e Biomateriais; 2016
Institución organizadora:
SLABO
Resumen:
Small-diameter tubular structures with potential application as vascular grafts (VG) scaffolds should present compliant response, porous architecture, biocompatibility and bioresorbability. Electrospinning is an attractive technique to tailor VG into the desire structure, size and properties. The use of biomaterials composed of synthetic poly(L-lactic acid) (PLLA) and segmented poly(ester urethane) (PHD) could result in biomimetic VGs because of their collagen and elastin-like mechanical responses, respectively. The hydrolytic degradation and mechanical response of electrospun bilayered VG made of PLLA-PHD blends were evaluated.PLLA solution (10% wt/v) in DMF/THF and PHD (25 % wt/v) in TFE and two blends, 90/10 and 50/50, were electrospun after setting appropriate processing conditions. Sequential electrospinning was performed using a 5 mm diameter rotating mandrill to obtain bilayered VGs. The hydrolytic degradation was followed by GPC, FTIR, DSC, SEM and contact angle. The low initial crystallinity and high hydrophilicity of blends, along with a synergetic outcome produced by blending, led to a higher molecular weight loss. VG degraded evenly as a whole, with degradation time matching the required one for the regeneration processes.VG were subjected to pulsatile pressure cycles in a bioreactor under physiological conditions. The diameter variation was measured by sonomicrometry and elasticity assessment was performed by pressure-strain modulus and dynamic compliance. PLLA electrospun grafts showed stiff response capable of withstanding elevated pressures, while PHD grafts presented a more elastomeric behavior. The bilayered VG stiffness increased with internal pressure displaying a J-shaped pressure-diameter response in the extended physiological range. Electrospun bioresorbable VG showed a promising biomimetic mechanical behavior for vascular tissue engineering. Sonomicrometry technique could also be applied directly in in vivo experiences.